Regulator for dynamo-electric machines



(Nb Model.)

W. $TAN-LBY, Jr.

REGULATOR FOR DYNAMO ELECTRIC MACHINES. No. 435,982. Patented Sept. 9, 1890.

Q lint- UNITED STATES PATENT OFFICE.

\VILLIAM STANLEY, JR, OF GREAT BARRINGTON, MASSACHUSETTS.

REGULATOR FOR DYNAMO-ELECTRIC MACHINES.

SPECIFICATION forming part of Letters Patent No. 435,982, dated September 9, 1890. I Application filed October 17, 1888. Renewed April 26, 1890- Serial No. 349,613. (No model.)

To all whom it may concern.-

Be it known that 1, WILLIAM STANLEY, Jr., a citizen of the United States, residing in Great Barrington, in the county of Berkshire and State of Massachusetts, have invented certain new and useful Improvements in Dynamo-Electric Machines, of which the following is a specification.

My invention is applicable to any of the well-known forms of dynamo-electric generators having fields of simple curvature; and the object of my improvements is to provide means for keeping the diameter of commutation in a fixed position upon the commutator and at the same time maintaining a constant difference of potential between the terminals of the generator. It is well known that when a dynamo is in operation the diameter of commutation or neutral line is shifted forward from the position which it occupies when no current is being taken from the armature, so that in order to avoid sparking the brushes have to be shifted a distance proportional to the current generated.

By means of my invention I obviate the necessity of shifting the brushes, and at the same time am enabled to maintainaconstant electro-motive force at the terminals of the generator.

In carrying my invention into effect I join the pole-pieces of the generator by iron plates or bridges, thus completely surrounding the armature with iron and providing a magnetic shunt between the pole-pieces. Around the bridges and parallel to the shaft of the generator is wound a coil of wire, which crosses the bridges in a plane forming an angle with the diameter of commutation, and is connected in series with the armature-coils. This coil I call the distortion-coil. The flow of current through it opposes the passage of the lines of force between the pole-pieces through the magnetic shunt, compelling them to pass through the armature and determining their direction. Thus the position of the neutral line or diameter of commutation is fixed and the additional effectivelines of force assist in developing electro-motive force in the armature-coils. If the parts be so proportioned that the additional electro-motive force thus developed shall be at all times equal to that required to overcome the resistance'of the armature-coils and distortion-coil, then the electro-motive force at the terminals of the generator will be constant.

The invention is illustrated in the draw ings, in which the same letters of reference indicate corresponding parts throughout.

Figure 1 shows an end elevation of the dynamo; Fig. 2, a top elevation; Fig. 3, a vertical section through the line 00min Fig. 1. Fig. 4 is a section of the pole-pieces and the bridges connecting them, and Fig. 5 a diagram showing the connections of the various coils.

A A are the pole-pieces of the dynamo; B B, the field-coils, and O the armature. The polepieces are connected above and below the armature by the oast-iron bridges D D, which are held in place by the bolts (Z d. The polepieces A A, together with the bridges D D, completely surround the armature. Along the bridges D D outside of the armature is laid the distortion-coil E parallel with the shaft S. The plane in which the coil E lies forms an angle with the diameter of commutation, the coil being removed from the normal position of the neutral line in the opposite direction from that in which the brushes usually have to be advanced from it and to approximately the same distance. It will be evident that the position of the coil E determines the direction of the lines of force, which by its action are compelled to pass through the armature, and a neutral field will be created in the plane in which it lies, the position of which will be constant, thus fixing the position of the diameter of commutation and obviating the necessity of moving the collecting-brushes to correspond therewith. This method of keeping the position of the diameter of commutation constant also forms part of my invention, and is hereinafter claimed.

The coil E should be so proportioned, as may readily be done by those skilled in the art, that the additional electro-motive force developed in the armature-coils byits action shall equal or somewhat exceed that required to overcome the internal resistance of the machine, including the resistance of the coil E itself. A constant electro-motive force will then be maintained at the terminals of the generator.

What I claim as new, and desire to secure by Letters Patent, is-

1. In an electric-current generator, a magnetic shunt between the pole-pieces of the field-magnets around the armature and in combination therewith, a coil of wire surrounding the armature and operating to oppose the passage of lines of force from the field through the shunt and to compel them to enter the armature at points determined by the position of such coil.

2. In an electric-current generator, the combination of bridges of magnetic material connecting the pole-pieces of the fieldqnagnets,

and together with the pole-pieces forming a closed magnetic circuit about the armature, and a coil of Wire connected in series with the armature-coils, crossing the bridges in a direction parallel with the shaft of the machine, and at points removed from the normal position of the diameter of commutation in the opposite direction from that in Which the brushes ordinarily have to be removed from such position.

3. In an electric-current generator, the combination of bridges of magnetic material connecting the pole-pieces of the field-magnets,

and together with the pole-pieces forming a closed magnetic circuit about the armature, and a coil of wire connected in series with the armature-coils, crossing the bridges in a direction parallel with the shaft of the machine and at points removed as far and in opposite direction from the normal position of the diameter of commutation as the brushes are usually removed therefrom when the machine is in operation.

4:. The method of keeping in a fixed position the diameter of commutation in a dynamo electric machine, which consists in first providing a path for a portion of the lines of force between the field-magnets, and, second, compelling these lines to enter the armature in such a direction as to establish a neutral region at points approximately as far behind the normal position of the diameter of commutation as the brushes ordinarily have to be advanced ahead of such position, substantially as set forth.

In testimony whereof I have hereunto subscribed by name this 12th day of September, A. D. 1888.

WILLIAM STANLEY, J'R.

Witnesses:

JOHN H. KELMAN, MICHAEL LEAVY. 

